Emulating coherent backscattering in multipath tunnel systems on a near-term Quantum computer

TL;DR

This paper demonstrates how a quantum device can emulate coherent backscattering and weak localization phenomena in multipath tunnel systems, revealing phase effects and anti-localization behaviors.

Contribution

It introduces a method to simulate multipath quantum interference using superconducting qubits with engineered scattering centers and tunnel barriers.

Findings

Observation of Aharonov-Bohm oscillations in a quantum ring and tube.

Demonstration of weak anti-localization with long coherence times.

Angle dependence confirms stability and phase reversal in the two-path circuit.

Abstract

Superconducting qubits already demonstrated potential in emulating coherent back scattering or weak localization (WL) and tunnelling phenomena however, in a real multipath system they have not been verified yet.Here we show how a double-path system can be emulated by a quantum device through construction of multiple scattering centers in closed paths (detune boxes) and tunnel barriers with a large return probability (Pr) of electrons. Incorporation of such arrangements of tunnel barriers can add an extra geometric phase and demonstrate Aharonov-Bohm type oscillations (phi)0 and (phi/2)0 in a ring and a tube, respectively. A combination of inter and intra layer tunnelling in a double-path circuit creates a phase reversal and subsequently weak anti-localization (WAL) effect with a long coherence time. Finally, angle dependence of Pr firmly establishes stability of the two-path circuit which is also associated with a phase reversal due to the inter-path resonance.